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diff --git a/man3/exec.3 b/man3/exec.3 deleted file mode 100644 index caf6d6a..0000000 --- a/man3/exec.3 +++ /dev/null @@ -1,311 +0,0 @@ -'\" t -.\" Copyright (c) 1991 The Regents of the University of California. -.\" All rights reserved. -.\" -.\" SPDX-License-Identifier: BSD-4-Clause-UC -.\" -.\" @(#)exec.3 6.4 (Berkeley) 4/19/91 -.\" -.\" Converted for Linux, Mon Nov 29 11:12:48 1993, faith@cs.unc.edu -.\" Updated more for Linux, Tue Jul 15 11:54:18 1997, pacman@cqc.com -.\" Modified, 24 Jun 2004, Michael Kerrisk <mtk.manpages@gmail.com> -.\" Added note on casting NULL -.\" -.TH exec 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -execl, execlp, execle, execv, execvp, execvpe \- execute a file -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <unistd.h> -.P -.B extern char **environ; -.P -.BI "int execl(const char *" pathname ", const char *" arg ", ..." -.B " /*, (char *) NULL */);" -.BI "int execlp(const char *" file ", const char *" arg ", ..." -.B " /*, (char *) NULL */);" -.BI "int execle(const char *" pathname ", const char *" arg ", ..." -.BI " /*, (char *) NULL, char *const " envp "[] */);" -.BI "int execv(const char *" pathname ", char *const " argv "[]);" -.BI "int execvp(const char *" file ", char *const " argv "[]);" -.BI "int execvpe(const char *" file ", char *const " argv \ -"[], char *const " envp "[]);" -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR execvpe (): -.nf - _GNU_SOURCE -.fi -.SH DESCRIPTION -The -.BR exec () -family of functions replaces the current process image with a new process -image. -The functions described in this manual page are layered on top of -.BR execve (2). -(See the manual page for -.BR execve (2) -for further details about the replacement of the current process image.) -.P -The initial argument for these functions is the name of a file that is -to be executed. -.P -The functions can be grouped based on the letters following the "exec" prefix. -.\" -.SS l - execl(), execlp(), execle() -The -.I "const char\ *arg" -and subsequent ellipses can be thought of as -.IR arg0 , -.IR arg1 , -\&..., -.IR argn . -Together they describe a list of one or more pointers to null-terminated -strings that represent the argument list available to the executed program. -The first argument, by convention, should point to the filename associated -with the file being executed. -The list of arguments -.I must -be terminated by a null pointer, -and, since these are variadic functions, this pointer must be cast -.IR "(char\ *) NULL" . -.P -By contrast with the 'l' functions, the 'v' functions (below) specify the -command-line arguments of the executed program as a vector. -.\" -.SS v - execv(), execvp(), execvpe() -The -.I "char\ *const argv[]" -argument is an array of pointers to null-terminated strings that -represent the argument list available to the new program. -The first argument, by convention, should point to the filename -associated with the file being executed. -The array of pointers -.I must -be terminated by a null pointer. -.SS e - execle(), execvpe() -The environment of the new process image is specified via the argument -.IR envp . -The -.I envp -argument is an array of pointers to null-terminated strings and -.I must -be terminated by a null pointer. -.P -All other -.BR exec () -functions (which do not include 'e' in the suffix) -take the environment for the new process -image from the external variable -.I environ -in the calling process. -.SS p - execlp(), execvp(), execvpe() -These functions duplicate the actions of the shell in -searching for an executable file -if the specified filename does not contain a slash (/) character. -The file is sought in the colon-separated list of directory pathnames -specified in the -.B PATH -environment variable. -If this variable isn't defined, the path list defaults to -a list that includes the directories returned by -.I confstr(_CS_PATH) -(which typically returns the value "/bin:/usr/bin") -and possibly also the current working directory; -see NOTES for further details. -.P -.BR execvpe () -searches for the program using the value of -.B PATH -from the caller's environment, not from the -.I envp -argument. -.P -If the specified filename includes a slash character, then -.B PATH -is ignored, and the file at the specified pathname is executed. -.P -In addition, certain errors are treated specially. -.P -If permission is denied for a file (the attempted -.BR execve (2) -failed with the error -.BR EACCES ), -these functions will continue searching the rest of the search path. -If no other file is found, however, -they will return with -.I errno -set to -.BR EACCES . -.P -If the header of a file isn't recognized (the attempted -.BR execve (2) -failed with the error -.BR ENOEXEC ), -these functions will execute the shell -.RI ( /bin/sh ) -with the path of the file as its first argument. -(If this attempt fails, no further searching is done.) -.P -All other -.BR exec () -functions (which do not include 'p' in the suffix) -take as their first argument a (relative or absolute) pathname -that identifies the program to be executed. -.SH RETURN VALUE -The -.BR exec () -functions return only if an error has occurred. -The return value is \-1, and -.I errno -is set to indicate the error. -.SH ERRORS -All of these functions may fail and set -.I errno -for any of the errors specified for -.BR execve (2). -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR execl (), -.BR execle (), -.BR execv () -T} Thread safety MT-Safe -T{ -.na -.nh -.BR execlp (), -.BR execvp (), -.BR execvpe () -T} Thread safety MT-Safe env -.TE -.SH VERSIONS -The default search path (used when the environment -does not contain the variable \fBPATH\fR) -shows some variation across systems. -It generally includes -.I /bin -and -.I /usr/bin -(in that order) and may also include the current working directory. -On some other systems, the current working is included after -.I /bin -and -.IR /usr/bin , -as an anti-Trojan-horse measure. -The glibc implementation long followed the traditional default where -the current working directory is included at the start of the search path. -However, some code refactoring during the development of glibc 2.24 -.\" glibc commit 1eb8930608705702d5746e5491bab4e4429fcb83 -caused the current working directory to be dropped altogether -from the default search path. -This accidental behavior change is considered mildly beneficial, -and won't be reverted. -.P -The behavior of -.BR execlp () -and -.BR execvp () -when errors occur while attempting to execute the file is historic -practice, but has not traditionally been documented and is not specified by -the POSIX standard. -BSD (and possibly other systems) do an automatic -sleep and retry if -.B ETXTBSY -is encountered. -Linux treats it as a hard -error and returns immediately. -.P -Traditionally, the functions -.BR execlp () -and -.BR execvp () -ignored all errors except for the ones described above and -.B ENOMEM -and -.BR E2BIG , -upon which they returned. -They now return if any error other than the ones -described above occurs. -.SH STANDARDS -.TP -.B environ -.TQ -.BR execl () -.TQ -.BR execlp () -.TQ -.BR execle () -.TQ -.BR execv () -.TQ -.BR execvp () -POSIX.1-2008. -.TP -.BR execvpe () -GNU. -.SH HISTORY -.TP -.B environ -.TQ -.BR execl () -.TQ -.BR execlp () -.TQ -.BR execle () -.TQ -.BR execv () -.TQ -.BR execvp () -POSIX.1-2001. -.TP -.BR execvpe () -glibc 2.11. -.SH BUGS -Before glibc 2.24, -.BR execl () -and -.BR execle () -employed -.BR realloc (3) -internally and were consequently not async-signal-safe, -in violation of the requirements of POSIX.1. -.\" https://sourceware.org/bugzilla/show_bug.cgi?id=19534 -This was fixed in glibc 2.24. -.\" -.SS Architecture-specific details -On sparc and sparc64, -.BR execv () -is provided as a system call by the kernel -(with the prototype shown above) -for compatibility with SunOS. -This function is -.I not -employed by the -.BR execv () -wrapper function on those architectures. -.SH SEE ALSO -.BR sh (1), -.BR execve (2), -.BR execveat (2), -.BR fork (2), -.BR ptrace (2), -.BR fexecve (3), -.BR system (3), -.BR environ (7) |